State;
Key;
Laboratory;
on;
Integrated;
Optoelectronics/Tsinghua;
National;
Laboratory;
for;
Information;
Science;
and;
Technology,;
Department;
of;
Electronic;
Engineering,;
Tsinghua;
University,;
Beijing;
100084,;
China;
DQPSK; 偏振复用; 差分检测; 信号传输; NRZ; Gb; 标准单模光纤; 正交相移键控;